Interfacial structural crossover and hydration thermodynamics of charged C 60 in water
Interfacial structural crossover and hydration thermodynamics of charged C 60 in water
复制标题
带电C 60 在水中的界面结构交换和水化热力学
DOI：
10.1039/c8cp05422c
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发表时间：
2018
影响因子：
3.3
通讯作者：
Matyushov, Dmitry V.
中科院分区：
文献类型：
--
作者：
Sarhangi, Setare Mostajabi;Waskasi, Morteza M.;Hashemianzadeh, Seyed Majid;Matyushov, Dmitry V.
本研究采用经典分子动力学方法模拟了荷电富勒烯水合壳中水的水合热力学、结构和动力学。富勒烯的充电导致水合壳层的结构转变，伴随着产生大量指向溶质的悬空O-H键。与公认的结构-功能范式相反，这种界面结构转变对水合水的动力学或溶剂化热力学几乎没有影响。尽管在水化壳层中发生了显著的结构变化，但对溶质电荷的线性响应仍然保持不变，并且溶剂化热力学势对改变的结构几乎不敏感。只有溶剂化热容量，这是更高的热力学衍生物的溶剂化自由能，表明一些敏感性的局部水化结构。将溶剂化热力学势分解为溶质-溶剂间的直接相互作用和水化壳层的重构，并分析了静电相互作用和非极性相互作用对溶剂化热力学的相对贡献。
Classical molecular dynamics simulations of the hydration thermodynamics, structure, and dynamics of water in hydration shells of charged buckminsterfullerenes are presented in this study. Charging of fullerenes leads to a structural transition in the hydration shell, accompanied by creation of a significant population of dangling O–H bonds pointing toward the solute. In contrast to the well accepted structure–function paradigm, this interfacial structural transition causes nearly no effect on either the dynamics of hydration water or on the solvation thermodynamics. Linear response to the solute charge is maintained despite significant structural changes in the hydration shell, and solvation thermodynamic potentials are nearly insensitive to the altering structure. Only solvation heat capacities, which are higher thermodynamic derivatives of the solvation free energy, indicate some sensitivity to the local hydration structure. We have separated the solvation thermodynamic potentials into direct solute–solvent interactions and restructuring of the hydration shell and analyzed the relative contributions of electrostatic and nonpolar interactions to the solvation thermodynamics.